Grab bucket



l Feb. 13, 1923. Q

G. E. MELLIN GRAB BUCKET Filed May 25 1921 2 heets-sheet 1 zmmw Feb. 13, 1923. 1,444,800 G. E. MELLI N GRAB BUCKET Filed May 25, 1921 2 sheets-sheet 2 IIVVENTOR UORIVEYS Patented Feb. 13, 1923.

one stars GEORGE MELLIN; or wns'rnsrinren, New YORK, essrenon, BY Mnsnn ASSIGN- MENTS, TO 0. W. HUNT COMPANY, INC.

NEW YORK Application. filed May 25,

T 0 all 10 ham it may concern Be it known that I, GEORGE E. MELLIN, a citizen of the United States, residing in Vesterleigh, in the borough of Richmond, of the city of New York, in the State of New York, have invented certain new and useful Improvements in Grab Buckets, of which the following is a specification, reference being had to the accompanying drawings, forming a part hereof.

This invention has for its object to eliminate the binding and chafing in the ropes of grab buckets and the like. Heretofore, this problem has been met by attempts to minimize the binding and chafing rather than to eliminate them. In accordance with the present invention the usual upper and lower sheaves are laid out in such geometrical relation to one another and to the strands of rope that binding and chafing are eliminated. Broadly, this result is secured by making the lower sheaves of difierent diameters and laying them out on a circle having a pitch diameter which coincides with the circle on which the upper sheaves are laid out. The axis of the lower sheaves is inclined with respect to the axis of the upper sheaves and each off-going and on-coming strand of rope is disposed vertically.

The invention will be described more fully hereinafter in connection with the embodiment illustrated in the accompanying drawings, in which- Figure 1 is a view in side elevation of an improved type of four-lead grab bucket wherein the upper and lower sheaves of the closing rope are constructed and mounted in accordance with the invention.

Figure 2 is a view in plan of the bucket shown in Figure 1.

Figure 3 is a view in end elevation thereof.

Figure 4 is a schematically developed view showing the relation of the various ropes and sheaves.

Figure 5 is a diagrammatic view in plan showing the relation of the upper and lower sheaves which embody the invention.

It will be understood as the description proceeds that the invention is not limited to the type of hoisting device in which it is incorporated nor to the number of ropes employed but for convenience it has been illustrated as incorporated in a four-lead grab bucket of very common form. In this type of bucket the head casting a has pivoted 01E IVE'W YORK, N. Y., A CORPORATION OF.

GRAB Booker.

192i. serial. 1a. 472,370.

thereon links Z) which are pivoted to scoops 0 carried pivotally on a common shaft at. One strand of the holding rope is indicated at c and this may pass around the block a on the head a. The closing rope is indicated at f. It passes around a lower sheave g, thence around an upper sheave h, down around a middle lower sheave 9, up over an upper sheave it, down under a third lower sheave g and thence up to any convenient anchorage. The three lower sheaves g, g, are all mounted parallel to one another on the shaft 0?. The two upper sheaves 71,, h are mounted parallel to one another on a shaft (4 in the casting (a This invention is concerned with the construction of and the relation between the various upper and lower sheaves whereby binding and chafing of the closing rope f are eliminated.

Reference is now to be had to Figure 5 for an understanding of the layout of these sheaves. The middle one 9' of the three lower sheaves is of larger diameter than the other two sheaves g, 9 The two sheaves g, g are mounted on the shaft (Z with the middle sheave g and are parallel to it. They are laid out on a circle P having the same pitch diameter as the middle sheave g. The two upper sheaves h, h are of equal diameter and parallel and are mounted on the shaft a which is angularly inclined to the shaft cl supporting the lower sheaves. The upper sheaves h, h are laid out on a circle which coincides with the circle P on which the lower sheaves are laid out. The geometrical relation is indicated clearly in Figure 5. Physically, this layout results in the tangential alinement of grooves of the upper and lower sheaves. respectively, in such arrangement that each strand of the closing rope f going off one of the lower sheaves and coming on one of the upper sheaves is vertical. With these strands vertical there can be no chafingor binding.

The appended claims specify the relation of parts which constitutes the invention. No limitation on the scope thereof is to be imposed by reason of any other changes in parts which do not affect this relation.

I claim as my invention: 1. In grab buckets or the like, three parallel lower sheaves, the middle one being of greater diameter than the two outside ones, and two upper parallel sheaves, the lower sheaves being laid out on a circle having the pitch diameter of the middle sheave, and the upper sheaves being laid. out on acoincidingcircle having the same pitch diameter as said middle sheave.

2. In grab buckets or the like, three parallel lower sheaves, the middle one being of greater diameter than the two outside ones, a shaft on which said sheaves are rotatably mounted, the two outside sheaves being laid out on a circle having the same pitch diameter as the middle sheave, two upper par allel. sheaves, and a shaft on which said upper sheaves are mounted rotatably and angularly inclined to said lower shaft, said upper sheaves being laid out on a circle having the same pitch diameter as the lower sheave and coinciding therewith.

This specification signed this 19th day of May, A. 1)., 1921.

GEORGE E. MELLIN. 

